Spindle force actuator

Abstract

An apparatus includes a circuit, a code modulator, and an actuator. The circuit is operable to detect displacements of a rotating object while in motion. The circuit is operable to detect a position of the displacements and to generate a signal associated therewith. The code modulator is operable to generate a modulated signal based on the position and the displacements. The actuator is operable to apply a force to the rotating object, wherein the force is based on the modulated signal.

What is claimed is: 
     
       1. An apparatus comprising:
 a sensor board comprising a plurality of sensors configured to detect displacements of a spindle motor in motion and a rotational position of an electrical field, and wherein the sensor board is configured to filter out stationary information associated with the spindle motor comprising a shape of the electrical field and a shape of the spindle motor; 
 a filter configured to receive the detected displacements and the rotational position of the electrical field, wherein the filter is further configured to determine and output an instantaneous velocity and a force based on the detected displacements and the rotational position of the electrical field; and 
 an actuator configured to receive the output from the filter and further configured to apply a force substantially opposite and equal in value to the determined force to the spindle motor. 
 
     
     
       2. The apparatus of  claim 1  further comprising:
 a converter coupled to the plurality of sensors, wherein the converter is configured to determine respective positions of the detected displacements. 
 
     
     
       3. The apparatus of  claim 1 , wherein the plurality of sensors is selected from the group consisting of a hall sensor, a charge coupling sensor, and a microphone. 
     
     
       4. The apparatus of  claim 1 , wherein the actuator is selected from the group consisting of an air jet, a piezo element, and an electromagnet. 
     
     
       5. The apparatus of  claim 1 , wherein the actuator is an electromagnet actuator and comprises odd and even coils wound clockwise and counterclockwise. 
     
     
       6. The apparatus of  claim 1 , wherein a gap between the actuator and the plurality of sensors ranges between 0.1 mm to 1.0 mm. 
     
     
       7. The apparatus of  claim 1 , wherein the filter comprises a decimation filter. 
     
     
       8. The apparatus of  claim 1  further comprising:
 a plurality of switches, wherein each switch of the plurality of switches is associated with a coil winding associated with a tooth of the actuator, and wherein switches of the plurality of switches turn on and off responsive the output from the filter to apply a force substantially opposite and equal in value to the determined force to the motor. 
 
     
     
       9. The apparatus of  claim 1  further comprising a sigma delta component coupled to the plurality of sensors, wherein the sigma delta component is configured to determine respective positions of the detected displacements. 
     
     
       10. A method comprising:
 detecting displacements of a motor in motion; 
 filtering out stationary information associated with the motor comprising a shape of an electrical field and a shape of the motor; 
 determining an instantaneous velocity and a force associated with the detected displacements from positions of the detected displacements and further from a position of a rotating electrical field; and 
 applying a force substantially opposite and equal in value to the determined force to the motor at the positions of the detected displacements. 
 
     
     
       11. The method of  claim 10  further comprising:
 determining positions of the detected displacements. 
 
     
     
       12. The method of  claim 10  further comprising:
 determining the position of the rotating electrical field. 
 
     
     
       13. The method of  claim 10 , wherein the applied force is an electromagnetic force.